Standing waves on arbitrary membrane

AI Thread Summary
The discussion centers on the feasibility of generating vibrational modes in a soap membrane stretched over an arbitrarily shaped closed loop of wire. The intuition presented suggests that such a setup could yield solutions to the 2D wave equation with zero-displacement conditions along the boundary. However, concerns are raised about the complexities of real-world membranes, which may not adhere strictly to the wave equation due to their elastic properties and ability to stretch. The idea is proposed that irregular boundaries could lead to fewer vibrational modes or wider frequency spacing. Ultimately, the viability of this intuition hinges on the interplay between the membrane's elasticity and the mathematical principles governing wave behavior.
the4thamigo_uk
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My (probably misguided) intuition says the following :

'Take a closed loop of wire and bend it into any arbitrary shape so that it lies flat on a table. stretch a membrane over it (i.e. a soap membrane say). Then, I should be able to vibrate it at just the right frequency to generate (at least) a fundamental mode of vibration.'

In other words I think my intuition is telling me that there are solutions to the 2D wave equation with a zero-displacement condition on an arbitrary closed boundary.

Is my intuition right or wrong? If wrong, why?

Also, my intuition is telling me that for a complicated irregular boundary that there would be fewer modes of vibration or that they would be spaced more widely apart in terms of frequency.

Thanks

Andy

Additional:

If the intuition is incorrect, then is this something to do with the fact that a real world membrane is elastic and can stretch in ways that don't satisfy the wave equation?
 
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I would think you'd generate several modes for different spatial scales that, in a real membrane, would quickly attenuate the whole membrane to the steady state as tey compete with each other.

A circle only has one spatial scale (the radius or diameter if you like), the arbitrary shape could have several.
 
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